In Chapter 5.4 of the Gnus Info manual (node "Customizing Articles") [1],
the variable `gnus-treat-play-sounds' is documented, but that variable is 
not in Emacs.

[1] info/gnus.info:9480: .

There is a change log entry from 2010-09-26 [2] that says

  * gnus-art.el (gnus-treat-play-sounds): Remove.

so I guess that variable no longer exists? In that case it just
needs removing from the manual and a patch (against master) is
attached inline below.

[2] lisp/gnus/ChangeLog.3:10348: .

Best regards,
N.


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